The deal also gives WhatsApp the power (and resources) to mount its biggest fight yet against the networks and traditional text messaging, but EU Commissioner Joaquin Almunia believes that the success of rival messaging services like Viber and Line won't lead to total WhatsApp domination.

"We have carefully reviewed this proposed acquisition and come to the conclusion that it would not hamper competition in this dynamic and growing market," Almunia said. "Consumers will continue to have a wide choice of consumer communications apps."

Reuters first reported that the deal would be cleared by the EU "unconditionally" on September 25, and Facebook will surely have expected it to get the go ahead without any issues — but the EU did send questionnaires to WhatsApp's rivals to in an effort to gauge the takeover's impact on the industry before deciding whether it should be approved.